It is a type of meridian in the human body, serving as the main pathway for the circulation of qi and blood within the body. This includes the hand taiyin lung meridian (LU), hand yangming large intestine meridian (LI), foot yangming stomach meridian (ST), foot taiyin spleen meridian (SP), hand shaoyin heart meridian (HT), hand taiyang small intestine meridian (SI), foot taiyang bladder meridian (BL), foot shaoyin kidney meridian (KI), hand jueyin pericardium meridian (PC), hand shaoyang triple energizer meridian (TE), foot shaoyang gallbladder meridian (GB), and foot jueyin liver meridian (LR). These twelve meridians are collectively known as the twelve meridians. Each meridian is directly connected to a specific zang-fu organ within the body, and there is a relationship of exterior-interior pairing among the various meridians.